ReedTable.h

#ifndef STK_REEDTABLE_H
#define STK_REEDTABLE_H
 
#include "Function.h"
 
namespace stk {
 
/***************************************************/
/***************************************************/
 
class ReedTable : public Function
{
public:
  ReedTable( void ) : offset_(0.6), slope_(-0.8) {};
 
 
  void setOffset( StkFloat offset ) { offset_ = offset; };
 
 
  void setSlope( StkFloat slope ) { slope_ = slope; };
 
  StkFloat tick( StkFloat input );
 
 
  StkFrames& tick( StkFrames& frames, unsigned int channel = 0 );
 
 
  StkFrames& tick( StkFrames& iFrames, StkFrames &oFrames, unsigned int iChannel = 0, unsigned int oChannel = 0 );
 
protected:
 
  StkFloat offset_;
  StkFloat slope_;
 
};
 
inline StkFloat ReedTable :: tick( StkFloat input )    
{
  // The input is differential pressure across the reed.
  lastFrame_[0] = offset_ + (slope_ * input);
 
  // If output is > 1, the reed has slammed shut and the
  // reflection function value saturates at 1.0.
  if ( lastFrame_[0] > 1.0) lastFrame_[0] = (StkFloat) 1.0;
 
  // This is nearly impossible in a physical system, but
  // a reflection function value of -1.0 corresponds to
  // an open end (and no discontinuity in bore profile).
  if ( lastFrame_[0] < -1.0) lastFrame_[0] = (StkFloat) -1.0;
 
  return lastFrame_[0];
}
 
inline StkFrames& ReedTable :: tick( StkFrames& frames, unsigned int channel )
{
#if defined(_STK_DEBUG_)
  if ( channel >= frames.channels() ) {
    oStream_ << "ReedTable::tick(): channel and StkFrames arguments are incompatible!";
    handleError( StkError::FUNCTION_ARGUMENT );
  }
#endif
 
  StkFloat *samples = &frames[channel];
  unsigned int hop = frames.channels();
  for ( unsigned int i=0; i<frames.frames(); i++, samples += hop ) {
    *samples = offset_ + (slope_ * *samples);
    if ( *samples > 1.0) *samples = 1.0;
    if ( *samples < -1.0) *samples = -1.0;
  }
 
  lastFrame_[0] = *(samples-hop);
  return frames;
}
 
inline StkFrames& ReedTable :: tick( StkFrames& iFrames, StkFrames& oFrames, unsigned int iChannel, unsigned int oChannel )
{
#if defined(_STK_DEBUG_)
  if ( iChannel >= iFrames.channels() || oChannel >= oFrames.channels() ) {
    oStream_ << "ReedTable::tick(): channel and StkFrames arguments are incompatible!";
    handleError( StkError::FUNCTION_ARGUMENT );
  }
#endif
 
  StkFloat *iSamples = &iFrames[iChannel];
  StkFloat *oSamples = &oFrames[oChannel];
  unsigned int iHop = iFrames.channels(), oHop = oFrames.channels();
  for ( unsigned int i=0; i<iFrames.frames(); i++, iSamples += iHop, oSamples += oHop ) {
    *oSamples = offset_ + (slope_ * *iSamples);
    if ( *oSamples > 1.0) *oSamples = 1.0;
    if ( *oSamples < -1.0) *oSamples = -1.0;
  }
 
  lastFrame_[0] = *(oSamples-oHop);
  return iFrames;
}
 
} // stk namespace
 
#endif